Cool exhaust mod! Sweet thread.......
...
Cool exhaust mod! Sweet thread.......
...
2009 White Hot G8 GT (stock)
* SOLD * 222/230 .597/.600 114+4 EPS Cam, Patrick G ECM/TCM Tune, Roto-Fab CAI, HSRK, Yank 3200 Torque Converter,
Transmission Cooler, Kooks 1 3/4" LT Headers, high flow cats, stock mufflers, Billet Prototypes Catch Can, UD Pulley,
Ported Intake Manifold, Spohn Trailing Arms
407 RWHP & 365 RWTQ
Best Time: 12.517 @ 115.02mph w/ 1.97 60' time - (on stock 18" AS Tires)
I paid $160 for the stainless Magna flow X-pipe and the 409 stainless straight pipe. Another $50 to have it put in. It can be done for less with aluminized pipe and a little more with 304 stainless pipe.
I wanted the thermal qualities to match as close as possible so I used the exact same pipe as factory. (I pay attention to details like that.)
2009.5 G8 GT, Patrick G. tuned-389rwhp, 379tq
...your lack of faith disturbs me...
Here are the dyno results. While you can see that I made a solid 6-8rwhp/rwtq gain under the curve, I had some knock retard slip in around 5400 rpm that didn't allow the "after" graph to stay consistently above the "before" dyno run. Without the KR, the peak difference would have shown a 8-10rwhp gain. Peak torque gain was a 10 lb ft increase. The before power/torque was 336/346 and the after power/torque was 342/356. Thanks to Kurt Decker from LSX Performance Power Tuning for use of his dyno tonight. For around $100 in parts, this is a worthwhile mod, especially since it's drone free.
Mitch (Fatdaddy), my graph was an exact overlay of yours in hp and tq until the knock retard at 5400. Our vehicles are extremely similar in mods and power.
2013 Corvette Grand Sport A6 Forged LME 416, Greg Good ported TFS 255 LS3 heads, EPS 222/242 .629/.604" 121LSA cam, ECS Novi 1500 supercharger running 11psi, ARH 1 7/8" headers, NPP exhaust, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwhp on race gas, w/stock street manners.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads, FAST 102, 231/231 114LSA cam. 506rwhp/442rwtq.
11.413 @ 121.29mph 1/4 mile, 168.7mph Texas Mile (all performance stats from 2010).
2014 GMC Yukon Denali XL 6.2L Air Raid MIT, VVT tuned to the max w/EFI Live.
2000 Pewter Ram Air Trans Am M6 heads/cam 508rwhp/445rwtq, 183.093mph Texas Mile
LS1,LS2,LS3,LS7 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX drivability & dyno tuning: for appointment press here.
I am going to say that its a 2.5 inch pipe? i got my answer 2.25
Last edited by 616 of 933; 10-16-2009 at 03:16 AM.
GTO spares and jack kit 200 OBO
rear 17x9.5 rims 200 OBO
Thanks for taking the time to dyno this mod. I think a pair of Kooks midlengths are in my future now. Looking forward to more of your tests. Can't wait till you install one your spec'd cams...
Nice gain for such a small investment. you used 2.5 tubing and Fatdaddy used 2.25. do you think it matters which size is used? Is one size easier to install?
Are there different sizes of MF Tru-X? If so, which did you use?
Care to speculate what you might get from this mod with Kooks 1 7/8 mids and high-flow cats?
Grrrr8 job. Thanks.
3rd in Class, All-GM Nationals 2008 & 2009
Award of Excellence, All-GM Nationals 2010 & 2012
Celebrity Pick Award, All-GM Nationals 2010
G8Board.Com G8 of the Year, 2010
Inaugural G8Board.com G8 of the Month, January 2010
3rd in Class, WTW Fall Classic Pontiac Car Show 2013 & 2015
Top 40 / 487, 29th Annual Cruisin' to the Creek Car Show 2015
1st in Class, 6th Annual Southeast G8 Extravaganza, 2016
1st in Class, Wide Track Warriors Car Show, 2016
1st in Class, WTW Fall Classic Pontiac Car Show, Amelia Island, 2016
HSV E3 Bumper and Fenders
VMS DoD-Delete with heads
TVS1900
RCR Lunati 215/223 .609/.615 112+0
RCR TB
Kooks 1 7/8 Mids+SOLO Mach
Pedders V8 SuperCar Coilover Track II w/ STB
BMR Adj LCA, Toe links & trailing arms
ZL1 Brakes
Circle_D built 6L80E. 3.27 diff
Roto-Fab
Crazy Paul 5-Gauge Pod / Speedhut Gauges
A this power level, I don't think you'll see a gain or loss between 2.25" and 2.5" pipes. I chose 2.5" because I will be making above this power level in the future. Both pipes are equally easy to install. The Magnaflow X comes in a variety of sizes. I used 2.5" x 12" size.
I think the mid-length Kooks would add another 16-20 rwhp whereas the long tubes would add 20+.
2013 Corvette Grand Sport A6 Forged LME 416, Greg Good ported TFS 255 LS3 heads, EPS 222/242 .629/.604" 121LSA cam, ECS Novi 1500 supercharger running 11psi, ARH 1 7/8" headers, NPP exhaust, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwhp on race gas, w/stock street manners.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads, FAST 102, 231/231 114LSA cam. 506rwhp/442rwtq.
11.413 @ 121.29mph 1/4 mile, 168.7mph Texas Mile (all performance stats from 2010).
2014 GMC Yukon Denali XL 6.2L Air Raid MIT, VVT tuned to the max w/EFI Live.
2000 Pewter Ram Air Trans Am M6 heads/cam 508rwhp/445rwtq, 183.093mph Texas Mile
LS1,LS2,LS3,LS7 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX drivability & dyno tuning: for appointment press here.
Thank you. i'm going to look for a local shop to do the welding. It looks like the size of the X is a perfect match to the spacing of the stock pipes. It looks really clean.
3rd in Class, All-GM Nationals 2008 & 2009
Award of Excellence, All-GM Nationals 2010 & 2012
Celebrity Pick Award, All-GM Nationals 2010
G8Board.Com G8 of the Year, 2010
Inaugural G8Board.com G8 of the Month, January 2010
3rd in Class, WTW Fall Classic Pontiac Car Show 2013 & 2015
Top 40 / 487, 29th Annual Cruisin' to the Creek Car Show 2015
1st in Class, 6th Annual Southeast G8 Extravaganza, 2016
1st in Class, Wide Track Warriors Car Show, 2016
1st in Class, WTW Fall Classic Pontiac Car Show, Amelia Island, 2016
HSV E3 Bumper and Fenders
VMS DoD-Delete with heads
TVS1900
RCR Lunati 215/223 .609/.615 112+0
RCR TB
Kooks 1 7/8 Mids+SOLO Mach
Pedders V8 SuperCar Coilover Track II w/ STB
BMR Adj LCA, Toe links & trailing arms
ZL1 Brakes
Circle_D built 6L80E. 3.27 diff
Roto-Fab
Crazy Paul 5-Gauge Pod / Speedhut Gauges
Thanks, Patrick.
I'm still trying to figure out why GM put in the extra cats and that nasty crimp above the tunnel brace what a mess. A drop from 2.25" to 1 7/8" with a transition back to 2.25" is ugly. That's about a 25-30% drop in effective flow rate in that section alone.
I need to find a reputable shop in Austin TX to get this done. Anyone local have any tips?
2009.5 MSM/Onyx G8 GT premium/sport/sunroof
Wrenched and tuned by Reckart Performance Tuning in Cedar Park, TX USA
I think they reduced the size to get the flow rate high enough in DOD mode so that the resonators would be effective.
Last edited by G8V8; 03-10-2010 at 05:27 AM.
3rd in Class, All-GM Nationals 2008 & 2009
Award of Excellence, All-GM Nationals 2010 & 2012
Celebrity Pick Award, All-GM Nationals 2010
G8Board.Com G8 of the Year, 2010
Inaugural G8Board.com G8 of the Month, January 2010
3rd in Class, WTW Fall Classic Pontiac Car Show 2013 & 2015
Top 40 / 487, 29th Annual Cruisin' to the Creek Car Show 2015
1st in Class, 6th Annual Southeast G8 Extravaganza, 2016
1st in Class, Wide Track Warriors Car Show, 2016
1st in Class, WTW Fall Classic Pontiac Car Show, Amelia Island, 2016
HSV E3 Bumper and Fenders
VMS DoD-Delete with heads
TVS1900
RCR Lunati 215/223 .609/.615 112+0
RCR TB
Kooks 1 7/8 Mids+SOLO Mach
Pedders V8 SuperCar Coilover Track II w/ STB
BMR Adj LCA, Toe links & trailing arms
ZL1 Brakes
Circle_D built 6L80E. 3.27 diff
Roto-Fab
Crazy Paul 5-Gauge Pod / Speedhut Gauges